1. Field of the Invention
This invention relates to safety systems for automatic transmission vehicles and more particularly to a system whose primary function is to warn a driver when he has stopped his vehicle but failed to place the shift lever in park, where "park" means "latched park" so that the vehicle is properly restrained. The system includes subsidiary safety features which will become apparent as the description proceeds.
2. Background of the Invention
The patent to Mochida, U.S. Pat. No. 4,482,885, is representative of systems which sound an alarm when a driver prepares to leave a vehicle with the transmission selector lever not in park. There are prior numerous other examples, including applicant's own prior U.S. Pat. No. 5,015,991, of alarms which are sounded when the driver is remiss in attending to matters affecting the safety of a vehicle presumably parked in a non-lethal condition. For example, alarms are sounded to remind a driver to remove the keys, to set the emergency brake, to turn off lights, etc., but in common with all of these is the fact that only alarms, visible and/or audible, are depended upon to remind the driver to put matters to right before he leaves the vehicle. The problem with alarms alone is the fact that a driver becomes so used to them that he simply ignores them. While in most instances, e.g. when parking on a level street, ignoring an alarm may lead to no danger, there are occasions when this is not so, e.g., parking on a slope. Thus there is a need for a system which does more than merely signal an alarm but rather forcibly calls the attention of the driver to an alarm to put matters to right before he leaves the vehicle immobilized.
The broad object, therefore, of the invention is to provide a system for automatic transmission vehicles whose function is to sound alarms calling attention to the oversight or to vehicle derangement while the driver is forcibly reminded to give heed to the alarms before he is able to leave the vehicle.